Preparation of diazo baths suitable for the production of azo dyestuffs



Patented Oct. 4, 1932 UNITED? STATES PATENT; OFFICE CARL TAUIBE, 0F LEVERKUSEN-ON-THE-RHINE, GERMANY, ASSIGNOR TO GENERAL ANILINE WORKS; INC., OF NEW YORK,

N. 'Y., A CORPORATION OF DELAWARE I'RnraBATIonor DIAZO BATES SUITABLE FOR THE PRODUCTION or AZO nYnsTUrrs on THE FIBER I d No Drawing. Application filed February 21, 1929, Serial No. 341,837, and in Germany February 25, 1928.

The present invention relates to an improvement in the art of producing azo dyestuffs on the fiber. y

' As is known, stable diazo compounds, in-

sensitive to more elevated temperatures ofier great interest in naphthol red dyeing,.particularly on account of the convenient method of working. i I

According to the present invention, the

wherein R and R stand for alkyl, or cyclo-v hexyl, or R and R jointly-stand for a pentaamine, diethylamine, cyclohexyl-alkylamine, are used for producing azo dyestuffs on the fiber, especially on the vegetable fiber. The condensation products from the diazo compounds and the secondary amines are obtainable according to'the process described by Bayer and Jaeger in Berichte der Deutschen Chemischen Gesellschaft, vol. 8, pages 148 and 893 and by Wallach in Liebigs Annalen -der Chemie vol. 235, page 233, by diazotizing in the usual manner with hydrochloric acid and sodium nitrite an aminocompound, and adding slowly the diazo solution to a solution of the secondary amine, advantageously with the addition of a caustic alkali, while stirring, eventually with cooling. The new condensation products separate in a crystal-, line form, or in the form of oils which on cooling solidify. They are generally white to yellowish colored, crystallizing substances with a low melting point. The condensation products used for the purpose of my invention may be illustrated by. the general forymula RN=N-N/ wherein R stands for a .benzene residue containing no sulfuric acid and no carboxylic condensation products of diazo compounds,

methylene chain, for example dimethylwhile they are decomposed quantitatively into their constituents even by cold dilute acids andaccordingly enable diazo solutions to be produced easily and quickly for technical purposes. I Y s The dyeings are produced in the follow- 'Ing manner: The material to be dyed is impregnated with a grounding liquor contain ing the coupling component, for example a 2.3-hydroxy-naphthoic acid arylide, ,B-naphthol or di-aceto-acetic-(tolidide) centrifugated or wrung out, and developed for about hourin adiaz'o bath prepared from a con-' densation product of a diazo compound with a secondary amine, the dyed material is rlnsed, s0aped,rinsed and dried.

Indyeing 50 grams of cotton yarn, the

grounding liquor is prepared by dissolving together about 5 gram to about 5 grams of the coupling component, about 1 to 10 com. of caustic soda lye of 34 B. and about 1 to about 10 com. of Turkey red oil of 50% .strength and making .up the whole with water to one'liter.

The developing bath is prepared by acidifyirfg about 1 gram to about 3 grams of the r above identified condensation products with concentrated or diluted hydrochloric acid,

for example by. stirring with about I to about 3 com. of hydrochloric acid of-22 B., making up the mixture with water to one liter and neutralizing the same with sodium acetate, for example by the addition of about 4 to about 20 com. of a sodium acetate solution of 20% strength; if desired common salt may be added to the solution.

The following examples serve to illustrate my invention without limiting it thereto Emamplel.4 grams .of 2.3-hydroxynaphthioc acid-o -naphthalide are dissolved inthe known manner with Turkey red oil and caustic soda lye to an aqueous solution of 1000 ccs. and 50 grams of cotton are impregnated in the customary manner with this solution for half an hour at about 30 C. The well centrifuged material is then developed in a bath, containing per liter 1.65 grams of the piperidine compound of'diazotized meta-nitro-o-toluidine. The piperidine compound is dissolved by producing a paste of the same with a small amount of alcohol or a customary wetting agent, adding 4 cos. of concentrated hydrochloric acid and, if necessary, -heating somewhat. The mixture is advantageously left to stand for a quarter of an hour and then diluted with waterto the required volume. After the excess of acid has been neutralized-Congo red paper should no longer be turned bluethe solution is ready for developing the dyestufi. A- red dyeing is produced corresponding to the red obtained from 2.3-hydroxynaphthoic acida-naphthalide and m-nitro-o-toluidine.

Eaample 2.-The materials are impregnated as describedin Example 1 and devel- L oped in a solution, containing per liter 3 grams of the piperidine compound of diazodianisidine, dissolved in the manner disclosed in Example .1. Towards the completion of the dyestufi' formation the acid is neutralized with sodium bicarbonate. A blue is produced.

Eaample 31-4 grams of 2.3-hydroxynaphthoic acid-,B-naphthalide are dissolved in, the

known manner with Turkey red oil and caustic soda lye to make a solution of 1000 cc. and 50 grams of cotton are impregnated in the customary manner with this solution for 1 35 half an hour at about 30 C. Thewell cen- "trifugedmaterial is then developed in a bath containingper liter.1.7 grams ofthe dimethylamine compound of diazotized 2-methyll-chloro-aniline. 0 pound is dissolved by producing a paste of the same with a small amount alcohol, adding 4 com. of concentrated hydrochloricacid.

Themixture is advantageously left to stand for a quarter of an hour and then diluted with water to 1 liter.

' The excess of acid is neutralized. by the addition. of sodium acetate solution of 20% strength-Congo red paper should no ,longer be turned .blueand the solution is now so ready for developing the dyestulf. A bluishred shade is obtained. 7 a Example 4. .50 grams of cotton are i111? '-pregnated with a ,B-naphthol-solution as described in Example 3, and developed in a The parts given in the following claims are by weight.

Iclaihiz- 1. The process of preparing diazo baths suitable for use in the art of producing azo The dimethylamine com- .prises acidifying a acidifying a compoundof the general forformula:

R--N=NN/ wherein R stands for a. radical of the benzene series containing no sulfonic acid and no carboxylic acid groups, and .R and R stand for alkyl groups, with hydrochloric acid, diluting the mixture with water and neutralizing'the same withsodium acetate.

3. The process of preparing diazo baths suitable for use in the art of producing azo dyestuffs on thefiber, which process comprises acidifying a compound of the general series containing no sulfonic acid and no carboxylic acid groups, with hydrochloric acid,- diluting the mixture with water and neutralizing' the same with sodium acetate.

4. The process of preparibg diazo suitable for use in the, art of producing azo. dyestufl's on the fiber, which process comcompound of the general formulaz- RN=NN \CH| wherein R stands for a benzene nucleus which may be substituted by halogen, alkyl-, alkoxybaths 1 oups, and R and R stand or nitro-groupswith hydrochloric acid, di-.

luting the mixture with water andneutralizing the same with sodium acetate.

5. The process of preparing diazo baths suitable for, use in the art of producing azo prises acidifying a compound of the general formpla: l

with hydrochloric acid,'dilutin the mixture with water and neutralizing t e same with dyestufi's on the fiber which process comprises s dium acetate.

. dyestufls on tl fiber, which prbcess com- 4 100 wherein R stands for a radical of the benzene 6. The process of preparingdiazo baths suitable for use in the art of producing azo dyestuifs on the fiber, whichoprocess comprises acidifying about 1 to 3 parts of a compound of'the general formula wherein R standsfor a radical of the benzene series containing no sulfonic' acid and no carboxylic acid groups, and R and R stand for alkyl, cyclohexyl, or R and R jointly stand for a penta-methylene chain, with concentrated hydrochloric acid, making up the mixture with water to about 1000 parts and neutralizing the same with sodium acetate.

7. The process of preparing diazo baths suitable for use in the art of producing azo dyestuifs on the fiber, which process comprises acidifying about l to 3 parts of a compound of the general formula:

R1 RN=N-N/ wherein R stands for a radical of the benzene series containing no sulfonic acid and no carboxylic acid groups, R and R stand for' alkyl groups, with concentrated hydrochloric acid, making up the mixture with water to about 1000 parts and neutralizing the same with sodium acetate.

prises'acidifying 1 to 3 parts of a compound of the formula:

my hand.

- CARL TAUBE. [L.s.]

8. The process of preparing diazo baths suitable for use in the art of producing azo dyestufis on the fiber, which process comprises acidifying about 1 to 3 parts of a compound of the general formula:

\ wherein R stands for aradical of the benzene series containing no sulfonic acid and no carboxylic acid groups, with concentrated hydrochloric acid, making up the mixture with water to about 1000 parts and neutralizing the same with sodium acetate.

9. The process of preparing diazo baths suitable for use in the art of producing azo dyestufi's on the fiber, which process comprises acidifying about 1 to 3 parts of a compound of the general formula:

wherein R stands for a benzene nucleus which may be substituted by halogen, alkyl-, alkoxyor nitro-groups, with concentrated hydrochloric acid, making up the mixture with water to about 1,000 parts and neutralizing the same with sodium acetate.

10. The process of preparing diazo baths suitable .for use in the art of producing azo dyestufl's on the fiber, which process com- 

